Btrfs: fix a mismerge in btrfs_balance()

Raid56 merge (merge commit e942f88) had mistakenly removed a call to
__cancel_balance(), which resulted in balance not cleaning up after itself
after a successful finish.  (Cleanup includes switching the state, removing
the balance item and releasing mut_ex_op testnset lock.)  Bring it back.

Reported-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 9ff454df6756..6b9cff42265d 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -3235,6 +3235,11 @@ int btrfs_balance(struct btrfs_balance_control *bctl,
                 update_ioctl_balance_args(fs_info, 0, bargs);
         }
 
+        if ((ret && ret != -ECANCELED && ret != -ENOSPC) ||
+            balance_need_close(fs_info)) {
+                __cancel_balance(fs_info);
+        }
+
         wake_up(&fs_info->balance_wait_q);
 
         return ret;